The present invention relates to vegetable harvesters, and especially to such harvesters adapted to harvest vegetables with appendages, such as onions. These appendages must be removed in harvesting.
No prior art onion harvester has achieved any significant degree of success. One machine which has achieved some commercial use is sold by Air-Flo Clipper Manufacturing Company, Inc. It is a machine which has to be pulled by a tractor. It digs a row of onions, and employs a large blower to blow the tops of the onions upwardly as they pass over the blower. The tops, being resistant to air flow, are lifted by the blower. They then pass beneath an oscillating type cutter which cuts the tops.
Unfortunately, onions do not all grow to the same size. As a result, they are topped unevenly in this device. Also, this device works satisfactorily only on onions grown in climates where the top can be dried out prior to harvest- ing.
In hot, sunny climates, the tops of the onions cannot be dried before harvesting. They must be harvested green. As a result, the tops of these onions are very full and bushy. It is difficult to blow these tops upright and clip them because they are so full.
Onions grown in such climates also have to develop large root systems. The Air-Flo machine makes no provision for eliminating the roots on these onions. The roots cannot be lifted by a flow of air since they are not sufficiently resistant to air flow.
A large pull type machine was developed in Israel in an attempt to harvest such onions. The user had to do a number of separate operations in order to use this harvester. First the onions had to be dug and left laying in the field. Then four rows had to be windrowed. Finally, the machine was pulled again through the field to top the onions. This machine proved totally ineffective.
Consequently, most onions are harvested manually, especially in the hotter climates where most of the onions are grown.